LlPassTouches

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Summary

Function: llPassTouches( integer pass );

Sets the pass-touches prim attribute.

• integer pass PASS_* flag

Whether Touches are passed to the root prim depends not only on which PASS_* flag is selected, but may also depend on if there is a script that in the prim that handles one of the touch events. For this reason most users will want to use PASS_ALWAYS or PASS_NEVER as they do not have this variable behavior.

The default value for this attribute is PASS_ALWAYS.

pass Constant Value touch Script No touch Script Description
PASS_IF_NOT_HANDLED 0 not passed passed Touches are passed if there is no script handling the event in the prim.
PASS_ALWAYS 1 passed passed Default: Touches are always passed to the root.
PASS_NEVER 2 not passed not passed Touches are never passed to the root.

Caveats

  • Has no known effect if called from within the root prim.
All Issues ~ Search JIRA for related Bugs

Examples

Make a two-prim LINK_SET (Object). Name the root "Parent" and the child "Child". To the root, add this script:
integer told;
 
default
{
    state_entry()
    {
        told = FALSE;
    }
    touch_start(integer total_number)
    {
        if(!(llDetectedLinkNumber(0) == llGetLinkNumber()))// We can use a condition like this to filter from which prims touches are triggered.
        {
            llSay(0, "My child tells me you touched it. Abuse report pending.");// This will only be spoken if the child is touched twice.
            told = TRUE;
        }
        else
        {
            if(!told)
                llSay(0, "You can touch me all you like");// The unaware Parent leads you on.
            else
                llSay(0, "If I had my way you would have your hands cut off!");// Not any more.
        }
    }
}

And to the child, add this script:

integer once_is_too_often;
default
{
    state_entry()
    {
        llPassTouches(FALSE);// Innocent child doesn't know to say something the first time.
        once_is_too_often = FALSE;
    }
    touch_start(integer total_number)
    {
        if(llDetectedLinkNumber(0) == llGetLinkNumber())// Again we check who is being touched.
        {
            if(!once_is_too_often)
            {
                llSay(0, "If you touch me again I'm telling.");
                llPassTouches(TRUE); // But if a second time, it will tell.
                once_is_too_often = TRUE;// And then fall silent.
            }
        }
    }
}

See Also

Events

•  touch_start
•  touch
•  touch_end

Functions

•  llPassCollisions

Deep Notes

TRUE & FALSE vs. PASS_* flags

Prior to Server Version 1.40.2, pass was couched in terms of being a boolean and the only meaningful values were 0 and 1. The best practice at that time was to use the integer constants TRUE and FALSE. The design of this function left much to be desired. The problem was that while TRUE always caused all Touches to be passed along to the the root, FALSE would only not pass Touches if there the prim had a script that handled a touch event. This meant to fully utilize this function the prim must contain a script that handled touch events! With the release of Server Version 1.40.2, the PASS_* flags were introduced and the subtype of the pass was changed. Specifically the introduction of PASS_NEVER solved this problem, allowing content creators to eliminate scripts that were only in the object to tweak the passing of touch events.

History

  • Introduction: ?
  • Change: SVC-5923 - Server version 1.40.2 - New pass value added: 2

All Issues

~ Search JIRA for related Issues
   Add enumeration to llPassCollisions() to provide PASS_ALWAYS, PASS_IF_NOT_HANDLED, and PASS_NEVER as explicit options.
(Was: Collisions passed to parent REGARDLESS llPassCollisions(FALSE) in child)

Signature

function void llPassTouches( integer pass );
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